Google provides a free service in which the data lives on Google servers and can be mined and destroyed at the will of google. We have seen cases where people have losed access to their data for really stupid and arbitrary reasons. If data is not critical, Google is a good choice.
Apple, with iToos and successors, provides a paid service in which contacts, calendars, mail, personal information, and files are synchronized among computers. In my experience over the past 10 years or so I have not lost data. Sometimes there has been issues, but I have had up to three computers in sync. In addition, I have been able to manage family computers remotely using Mobileme.
These are two different products, and unfortunately with the introduction of iOS, the toolchain became broken and Mobileme no longer worked as well as it did. So a good product is gone.
I see nothing that great about iCloud, except it is not google, so I have some level of confidence that my data is not be mined and advertisements are not going to be targeted based on email. iCloud no long synchs mail between Mac and iOS devices, which sucks. it no longer helps me manage passwords, which can cost $50 per device. OTOH, the App store now lets me share purchases across all macs.
I am not saying iCloud is good, it seems to suck. Mobileme really helped me manage data much more transparently than Google dropbox or anyone else. I also have a personal webdav server which I could use but it is not as transparent as Mobileme. Now that Mobileme is gone I might make it work.
What would make me a google fan is if they updated the Google Docs. This could be the new killer app for google. However, they are missing some quite fundamental features on the application. For examples, graphing has few advanced options, and the presentation cannot change slide size.